AILerp Class Reference

Linearly interpolating movement script. More...

Detailed Description

Linearly interpolating movement script.

This movement script will follow the path exactly, it uses linear interpolation to move between the waypoints in the path. This is desirable for some types of games. It also works in 2D.

Recommended setup:

This depends on what type of movement you are aiming for. If you are aiming for movement where the unit follows the path exactly (you are likely using a grid or point graph) the default settings on this component should work quite well, however I recommend that you adjust the StartEndModifier on the Seeker component: set the 'Exact Start Point' field to 'NodeConnection' and the 'Exact End Point' field to 'SnapToNode'.

If you on the other hand want smoother movement I recommend adding the Simple Smooth Modifier to the GameObject as well. You may also want to tweak the rotationSpeed.

Public Member Functions
void	FinalizeMovement (Vector3 nextPosition, Quaternion nextRotation)
virtual void	ForceSearchPath ()
	Requests a path to the target.
virtual Vector3	GetFeetPosition ()
void	MovementUpdate (float deltaTime, out Vector3 nextPosition, out Quaternion nextRotation)
	Calculate all movement for a single movement step and move the character.
void	OnDisable ()
virtual void	OnPathComplete (Path _p)
	Called when a requested path has finished calculation.
virtual void	OnTargetReached ()
	The end of the path has been reached.
virtual void	SearchPath ()
	Requests a path to the target.
float	TrySearchPath ()
	Tries to search for a path.
Public Member Functions inherited from IAstarAI
void	FinalizeMovement (Vector3 nextPosition, Quaternion nextRotation)
	Move the agent.
void	Move (Vector3 deltaPosition)
	Move the agent.
void	MovementUpdate (float deltaTime, out Vector3 nextPosition, out Quaternion nextRotation)
	Calculate how the character wants to move during this frame.
void	SearchPath ()
	Recalculate the current path.
void	Teleport (Vector3 newPosition, bool clearPath=true)
	Instantly move the agent to a new position.

Public Attributes
bool	canMove = true
	Enables or disables movement completely.
bool	canSearch = true
	Enables or disables recalculating the path at regular intervals.
bool	enableRotation = true
	If true, the AI will rotate to face the movement direction.
bool	interpolatePathSwitches = true
	If true, some interpolation will be done when a new path has been calculated.
float	repathRate = 0.5F
	Determines how often it will search for new paths.
bool	rotationIn2D = false
	If true, rotation will only be done along the Z axis so that the Y axis is the forward direction of the character.
float	rotationSpeed = 10
	How quickly to rotate.
float	speed = 3
	Speed in world units.
float	switchPathInterpolationSpeed = 5
	How quickly to interpolate to the new path.

Protected Member Functions
override void	Awake ()
	Initializes reference variables.
virtual Vector3	CalculateNextPosition (out Vector3 direction)
	Calculate the AI's next position (one frame in the future).
virtual void	ConfigureNewPath ()
	Finds the closest point on the current path and configures the interpolator.
virtual void	ConfigurePathSwitchInterpolation ()
virtual void	OnEnable ()
	Called when the component is enabled.
override int	OnUpgradeSerializedData (int version, bool unityThread)
	Handle serialization backwards compatibility.
IEnumerator	RepeatTrySearchPath ()
	Tries to search for a path every repathRate seconds.
virtual void	Start ()
	Starts searching for paths.
virtual void	Update ()

Protected Attributes
bool	canSearchAgain = true
	Only when the previous path has been returned should a search for a new path be done.
PathInterpolator	interpolator = new PathInterpolator()
float	lastRepath = -9999
	Time when the last path request was sent.
ABPath	path
	Current path which is followed.
Vector3	previousMovementDirection
Vector3	previousMovementOrigin
	When a new path was returned, the AI was moving along this ray.
float	previousMovementStartTime = -9999
Seeker	seeker
	Cached Seeker component.
Transform	tr
	Cached Transform component.

Properties
bool IAstarAI.	canMove [get, set]
	Enables or disables movement completely.
bool IAstarAI.	canSearch [get, set]
	Enables or disables recalculating the path at regular intervals.
Vector3 IAstarAI.	desiredVelocity [get]
Vector3	destination [get, set]
bool	hasPath [get]
bool	isStopped [get, set]
	Gets or sets if the agent should stop moving.
float IAstarAI.	maxSpeed [get, set]
	Max speed in world units per second.
System.Action	onSearchPath [get, set]
bool	pathPending [get]
Vector3 IAstarAI.	position [get]
	Position of the agent.
float	remainingDistance [get, set]
Quaternion IAstarAI.	rotation [get]
	Rotation of the agent.
Vector3 IAstarAI.	steeringTarget [get]
	Point on the path which the agent is currently moving towards.
Transform	target [get, set]
	Target to move towards.
bool	targetReached [get, set]
	True if the end of the current path has been reached.
Vector3 IAstarAI.	velocity [get]
Properties inherited from IAstarAI
bool	canMove [get, set]
	Enables or disables movement completely.
bool	canSearch [get, set]
	Enables or disables recalculating the path at regular intervals.
Vector3	desiredVelocity [get]
	Velocity that this agent wants to move with.
Vector3	destination [get, set]
	Position in the world that this agent should move to.
bool	hasPath [get]
	True if this agent currently has a path that it follows.
bool	isStopped [get, set]
	Gets or sets if the agent should stop moving.
float	maxSpeed [get, set]
	Max speed in world units per second.
System.Action	onSearchPath [get, set]
	Called when the agent recalculates its path.
bool	pathPending [get]
	True if a path is currently being calculated.
Vector3	position [get]
	Position of the agent.
float	remainingDistance [get]
	Remaining distance along the current path to the end of the path.
Quaternion	rotation [get]
	Rotation of the agent.
Vector3	steeringTarget [get]
	Point on the path which the agent is currently moving towards.
bool	targetReached [get]
	True if the agent has reached the end of the current path.
Vector3	velocity [get]
	Actual velocity that the agent is moving with.

Private Member Functions
void	Init ()
void IAstarAI.	Move (Vector3 deltaPosition)
	Move the agent.
Quaternion	SimulateRotationTowards (Vector3 direction)
void IAstarAI.	Teleport (Vector3 position, bool clearPath)

Private Attributes
Vector3	previousPosition1
Vector3	previousPosition2
Vector3	simulatedPosition
Quaternion	simulatedRotation
bool	startHasRun = false
	Holds if the Start function has been run.
Transform	targetCompatibility
	Required for serialization backward compatibility.

Member Function Documentation

override void Awake ( )

protectedvirtual

Initializes reference variables.

If you override this function you should in most cases call base.Awake () at the start of it.

Reimplemented from VersionedMonoBehaviour.

virtual Vector3 CalculateNextPosition ( out Vector3  direction )

protectedvirtual

Calculate the AI's next position (one frame in the future).

Parameters

direction

The tangent of the segment the AI is currently traversing. Not normalized.

virtual void ConfigureNewPath ( )

protectedvirtual

Finds the closest point on the current path and configures the interpolator.

virtual void ConfigurePathSwitchInterpolation ( )

protectedvirtual

void FinalizeMovement	(	Vector3	nextPosition,
		Quaternion	nextRotation
	)

virtual void ForceSearchPath ( )

virtual

Requests a path to the target.

Bypasses 'is-it-a-good-time-to-request-a-path' checks.

virtual Vector3 GetFeetPosition ( )

virtual

void Init ( )

private

void IAstarAI. Move ( Vector3  deltaPosition )

private

Move the agent.

Parameters

deltaPosition

Direction and distance to move the agent in world space.

This is intended for external movement forces such as those applied by wind, conveyor belts, knockbacks etc.Some movement scripts may ignore this completely (notably the AILerp script) if it does not have any concept of being moved externally.The agent will not be moved immediately when calling this method. Instead this offset will be stored and then applied the next time the agent runs its movement calculations (which is usually later this frame or the next frame). If you want to move the agent immediately then call:

ai.Move(someVector);
ai.FinalizeMovement(ai.position, ai.rotation);

void MovementUpdate	(	float	deltaTime,
		out Vector3	nextPosition,
		out Quaternion	nextRotation
	)

Calculate all movement for a single movement step and move the character.

This is called automatically unless canMove is false.

void OnDisable

(

)

virtual void OnEnable ( )

protectedvirtual

Called when the component is enabled.

virtual void OnPathComplete ( Path  _p )

virtual

Called when a requested path has finished calculation.

A path is first requested by SearchPath, it is then calculated, probably in the same or the next frame. Finally it is returned to the seeker which forwards it to this function.

virtual void OnTargetReached ( )

virtual

The end of the path has been reached.

If you want custom logic for when the AI has reached it's destination add it here. You can also create a new script which inherits from this one and override the function in that script.

override int OnUpgradeSerializedData ( int  version, bool  unityThread  )

protectedvirtual

Handle serialization backwards compatibility.

Reimplemented from VersionedMonoBehaviour.

IEnumerator RepeatTrySearchPath ( )

protected

Tries to search for a path every repathRate seconds.

See Also

TrySearchPath

virtual void SearchPath ( )

virtual

Requests a path to the target.

Some inheriting classes will prevent the path from being requested immediately when this function is called, for example when the AI is currently traversing a special path segment in which case it is usually a bad idea to search for a new path.

Quaternion SimulateRotationTowards ( Vector3  direction )

private

virtual void Start ( )

protectedvirtual

Starts searching for paths.

If you override this function you should in most cases call base.Start () at the start of it.

See Also

Init

RepeatTrySearchPath

void IAstarAI. Teleport ( Vector3  position, bool  clearPath  )

private

float TrySearchPath

(

)

Tries to search for a path.

Will search for a new path if there was a sufficient time since the last repath and both canSearchAgain and canSearch are true and there is a target.

Returns

The time to wait until calling this function again (based on repathRate)

virtual void Update ( )

protectedvirtual

Member Data Documentation

bool canMove = true

Enables or disables movement completely.

If you want the agent to stand still, but still react to local avoidance and use gravity: use isStopped instead.

See Also

canSearch

isStopped

bool canSearch = true

Enables or disables recalculating the path at regular intervals.

Setting this to false does not stop any active path requests from being calculated or stop it from continuing to follow the current path.Note that this only disables automatic path recalculations. If you call the SearchPath() method a path will still be calculated.

See Also

canMove

isStopped

bool canSearchAgain = true

protected

Only when the previous path has been returned should a search for a new path be done.

bool enableRotation = true

If true, the AI will rotate to face the movement direction.

bool interpolatePathSwitches = true

If true, some interpolation will be done when a new path has been calculated.

This is used to avoid short distance teleportation.

PathInterpolator interpolator = new PathInterpolator()

protected

float lastRepath = -9999

protected

Time when the last path request was sent.

ABPath path

protected

Current path which is followed.

Vector3 previousMovementDirection

protected

Vector3 previousMovementOrigin

protected

When a new path was returned, the AI was moving along this ray.

Used to smoothly interpolate between the previous movement and the movement along the new path. The speed is equal to movement direction.

float previousMovementStartTime = -9999

protected

Vector3 previousPosition1

private

Vector3 previousPosition2

private

float repathRate = 0.5F

Determines how often it will search for new paths.

If you have fast moving targets or AIs, you might want to set it to a lower value. The value is in seconds between path requests.

bool rotationIn2D = false

If true, rotation will only be done along the Z axis so that the Y axis is the forward direction of the character.

This is useful for 2D games in which one often want to have the Y axis as the forward direction to get sprites and 2D colliders to work properly.

float rotationSpeed = 10

How quickly to rotate.

Seeker seeker

protected

Cached Seeker component.

Vector3 simulatedPosition

private

Quaternion simulatedRotation

private

float speed = 3

Speed in world units.

bool startHasRun = false

private

Holds if the Start function has been run.

Used to test if coroutines should be started in OnEnable to prevent calculating paths in the awake stage (or rather before start on frame 0).

float switchPathInterpolationSpeed = 5

How quickly to interpolate to the new path.

Transform targetCompatibility

private

Required for serialization backward compatibility.

Transform tr

protected

Cached Transform component.

Property Documentation

bool IAstarAI. canMove

getsetprivate

Enables or disables movement completely.

If you want the agent to stand still, but still react to local avoidance and use gravity: use isStopped instead.

See Also

canSearch

isStopped

bool IAstarAI. canSearch

getsetprivate

Enables or disables recalculating the path at regular intervals.

Setting this to false does not stop any active path requests from being calculated or stop it from continuing to follow the current path.Note that this only disables automatic path recalculations. If you call the SearchPath() method a path will still be calculated.

See Also

canMove

isStopped

Vector3 IAstarAI. desiredVelocity

getprivate

Vector3 destination

getset

bool hasPath

get

bool isStopped

getset

Gets or sets if the agent should stop moving.

If this is set to true the agent will immediately start to slow down as quickly as it can to come to a full stop. The agent will still react to local avoidance and gravity (if applicable), but it will not try to move in any particular direction.The current path of the agent will not be cleared, so when this is set to false again the agent will continue moving along the previous path.This is a purely user-controlled parameter, so for example it is not set automatically when the agent stops moving because it has reached the target. Use targetReached for that.If this property is set to true while the agent is traversing an off-mesh link (RichAI script only), then the agent will continue traversing the link and stop once it has completed it.

Note

This is not the same as the canMove setting which some movement scripts have. The canMove setting disables movement calculations completely (which among other things makes it not be affected by local avoidance or gravity).

The steeringTarget property will continue to indicate the point which the agent would move towards if it would not be stopped.

float IAstarAI. maxSpeed

getsetprivate

Max speed in world units per second.

System.Action onSearchPath

getset

bool pathPending

get

Vector3 IAstarAI. position

getprivate

Position of the agent.

In world space.

See Also

rotation

float remainingDistance

getset

Quaternion IAstarAI. rotation

getprivate

Rotation of the agent.

In world space.

See Also

position

Vector3 IAstarAI. steeringTarget

getprivate

Point on the path which the agent is currently moving towards.

This is usually a point a small distance ahead of the agent or the end of the path.If the agent does not have a path at the moment, then the agent's current position will be returned.

Transform target

getset

Target to move towards.

The AI will try to follow/move towards this target. It can be a point on the ground where the player has clicked in an RTS for example, or it can be the player object in a zombie game.

Deprecated:

In 4.0 this will automatically add a AIDestinationSetter component and set the target on that component. Try instead to use the destination property which does not require a transform to be created as the target or use the AIDestinationSetter component directly.

bool targetReached

getset

True if the end of the current path has been reached.

Vector3 IAstarAI. velocity

getprivate

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The documentation for this class was generated from the following file:

• /Users/arong/Unity/a-pathfinding-project/Assets/AstarPathfindingProject/Core/AI/AILerp.cs